Thyroid Nodules and Cancer

Nodules

Discrete lesions within the thyroid gland that are radiologically distinct from the surrounding tissue

90%

What percentage of palpable nodules are benign?

colloid, multinodular goiter, Hashimoto’s thyroiditis, Cyst (simple, hemorrhagic), Follicular adenomas

What are the benign types of thyroid nodules?

Colloid nodule

What type of thyroid nodule is this - most common type, solid, well-defined, and usually non-functional?

Multinodular goiter

What type of thyroid nodule is this - nodules may be solid or cystic; occasionally hyperfunctional

Hashimoto’s thyroiditis

What type of thyroid nodule is this - autoimmune, diffuse changes in thyroid due to inflammation and fibrosis

cyst

What type of thyroid nodule is this - fluid filled can be simple (fluid only) OR complex (some solid parts)

follicular adenoma

What type of thyroid nodule is this - typically well encapsulated, solid, round, and well circumscribed

papillary carcinoma, follicular carcinoma, medullary carcinoma, anaplastic carcinoma, primary thyroid lymphoma, metastatic disease (secondary lesions)

What are the malignant thyroid nodules?

papillary carcinoma

What type of thyroid nodule is this - most common type of thyroid cancer (80%) and metastasizes via the lymphatics?

Follicular carcinoma

What type of thyroid nodule is this - 10-15% of thyroid cancers, good prognosis BUT higher chance of spreading (bones and lungs)?

Medullary thyroid cancer

What type of thyroid nodule is this - 4% of thyroid cancers; arises from C cells (parafollicular cells), metastasizes early, and is associated with MEN 2?

Anaplastic carcinoma

What type of thyroid nodule is this - rare, aggressive, 2% of thyroid cancers and the patient presents with rapidly enlarging mass and compressive symptoms?

primary thyroid lymphoma

What type of thyroid nodule is this - rare, associated with Hashimoto’s thyroiditis

lung, breast, kidney, melonoma

Which other cancers commonly metastasize to the thyroid

family hx of goiter, older women, soft, multinodular, high antibody titers, cystic on US, hot nodule on RAIU

What are some orange flags (low index of suspicion) for thyroid cacner?

Graves, toxic multinodular goiter, toxic adenoma

When evaluating for hyperthyroidism using RAIU what is associated with a high RAIU

thyroiditis, iodine overload, exogenous thyroid hormone use

When evaluating for hyperthyroidism using RAIU what is associated with a low RAIU

hx of radiation, young adults, family hx, elevated calcitonin, solid on U/S, cold nodule on RAIU, dark (hypoechoic) on U/S, irregular margins, microcalcifications, taller than wide, extrathyroidal extension, hard fixed nodule, vocal cord paralysis

Red flags for malignancy of thyroid nodules

Hx and physical, TSH, Free T4/T3, thyroid antibodies, U/S

Work up plan for thyroid nodules

wack on U/S, bigger than 1 cm

When is a FNA biopsy indicated for thyroid nodules?

The Bethesda system for reporting thyroid cytopathlogy (TBSRTC)

What is the rating system for FNA thyroid biopsies?

V, VI

TBSRTC ratings for malignancy

III, IV

TBSRTC for undetermined

II

TBSRTC for benign nodules

I

TBSRTC for nondiagnostic/nonsatisfactory

Women (3x)

What patient population is more likely to get thyroid cancer

total thyroidectomy (1+cm tumor), central neck dissection if lymphadenopathy is present

Treatment plan for papillary thyroid carcinoma

total thyroidectomy, RAI therapy if metastatic

Treatment plan for follicular thyroid carcinoma

lobectomy

Gameplan for small well differentiated cancers

total thyroidectomy

Game plan for larger tumors (1cm +) or more aggressive cancers

high risk patients, those with evidence of remaining thyroid tissue

Who gets radioactive iodine therapy after thyroidectomy?

levothyroxine forever (monitor levels and U/S)

If you remove the thyroid, you give the patient

90-95%

10 year survival rate for papillary carcinoma

85-95%

10 year survival rate of follicular carcinoma

70-90%

5 year survival rate of sporadic medullary thyroid carcinoma

Poor if not detected early

Prognosis of hereditary medullary thyroid carcinoma (MEN2)

<10%

1 year survival rate for anaplastic carcinoma